A bearing system includes a bearing, a shaft extending in the bearing, and a layer of nano-structured coating coated on one of the bearing and the shaft. A space is formed between the bearing and the shaft, and a lubricant is filled in the space. The lubricant is made of polymer material with hydrophilic and hydropholic properties. The nano-structured coating has a high surface tension which results in the coating being capable of adsorbing the lubricant to form a layer of lubricant film between the coating and the other of the bearing and the shaft, thereby reducing possibility of direct contact between the lubricant and the other of the shaft and the bearing. Thus, loss of the lubricant is reduced to avoid contacting frication between the shaft and the bearing. Accordingly, noise generated by the bearing system is decreased and life of the bearing system is extended.